43 lines
957 B
C
43 lines
957 B
C
/* SPDX-License-Identifier: MIT-0 */
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#define _GNU_SOURCE 1
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#include <assert.h>
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#include <stdio.h>
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#include <unistd.h>
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#include <systemd/sd-event.h>
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int main(int argc, char **argv) {
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pid_t pid = fork();
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assert(pid >= 0);
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/* SIGCHLD signal must be blocked for sd_event_add_child to work */
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sigset_t ss;
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sigemptyset(&ss);
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sigaddset(&ss, SIGCHLD);
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sigprocmask(SIG_BLOCK, &ss, NULL);
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if (pid == 0) /* child */
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sleep(1);
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else { /* parent */
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sd_event *e = NULL;
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int r;
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/* Create the default event loop */
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sd_event_default(&e);
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assert(e);
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/* We create a floating child event source (attached to 'e').
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* The default handler will be called with 666 as userdata, which
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* will become the exit value of the loop. */
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r = sd_event_add_child(e, NULL, pid, WEXITED, NULL, (void*) 666);
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assert(r >= 0);
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r = sd_event_loop(e);
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assert(r == 666);
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sd_event_unref(e);
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}
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return 0;
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}
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